Abstract
Marker chromosomes involving chromosome No. 1 were studied with banding techniques in 10 primary solid tumours. Structural or numerical aberrations of chromosome No. 1 were found in nine of these. Two major types of rearrangement of chromosome No. 1 were observed: translocation of the long arm (partial trisomy) and an isochromosome of 1q. Earlier chromosome studies and the present cases suggest that regions near the centromere and q21 are vulnerable points on human chromosome No. 1, and that region q21–32 is important for development of certain tumour types.